All of these (Erato, Mou, MarkdownLive) have noticeable lag while editing. I get that you have to parse and render the markdown, but with todays computing powe

All of these (Erato, Mou, MarkdownLive) have noticeable lag while editing. I get that you have to parse and render the markdown, but with todays computing power, is it too much to ask to see the text I just typed as soon as I press the keys? This is especially bad when there are images on the page. Why not just render the current block and leave the rest of the page as is.